drm/radeon/kms: fix resume regression for some r5xx laptops

commit f24d86f1a49505cdea56728b853a5d0a3f8e3d11 upstream.

I had removed this when I switched the atom indirect io methods
to use the io bar rather than the mmio bar, but it appears it's
still needed.

Reported-by: Mark Lord <kernel@teksavvy.com>
Signed-off-by: Alex Deucher <alexdeucher@gmail.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

diff --git a/drivers/gpu/drm/radeon/atom.c b/drivers/gpu/drm/radeon/atom.c
index 8e421f644a5435d44b6a0bc26f0edf3039b78c21..05efb5b9f13e841d265e3219d33e279e781de22f 100644 (file)
--- a/drivers/gpu/drm/radeon/atom.c
+++ b/drivers/gpu/drm/radeon/atom.c
@@ -112,6 +112,7 @@ static uint32_t atom_iio_execute(struct atom_context *ctx, int base,
                        base += 3;
                        break;
                case ATOM_IIO_WRITE:
+                       (void)ctx->card->ioreg_read(ctx->card, CU16(base + 1));
                        ctx->card->ioreg_write(ctx->card, CU16(base + 1), temp);
                        base += 3;
                        break;